Monday, 14 March 2011

Interval Training - Improve your speed

Interval Training

How to increase your aerobic and anaerobic capacity

Interval training is an effective training mechanism allowing athletes to target and improve specific energy systems appropriate to their sport. It is based on the principle that more work can be performed at higher exercise intensities with the same or less fatigue than continuous running.

Training can be completed in a controlled environment such as on a treadmill, exercise bike, rowing machine or cross trainer. However, as long as the session is structured, interval training can be just as effective on an appropriate sports pitch or court.

The table below provides a summary of the appropriate exercise intensities, times and rest periods required to train the phosphagen, glycolytic (anaerobic) or oxidative (aerobic) energy systems.

Maximum Effort %

Primary system stressed

Typical Exercise Duration

Ratio of effort to rest period.

90-100

Phosphagen (Anaerobic -ALACTIC)

5-10 seconds

1:12 to 1:20

75-90

Fast glycolysis (Anaerobic)

15-30 seconds

1:3 to 1:5

30-75

Fast glycolysis and oxidative

1-3 minutes

1:3 to 1:4

20-35

Oxidative (Aerobic)

> 3 minutes

1:1 to 1:3

Aerobic capacity

Aerobic capacity is the ability to maintain a high work output for a long period of time, while anaerobic capacity is the ability to perform very high workloads repeatedly. It is essential to train aerobic capacity as individuals with high baseline endurance are more resistant to fatigue and will have a faster recovery. This is supported by research, which found that tennis groundstroke hitting accuracy decreased by 69% from rest to volitional fatigue, while service accuracy decreased by30%.

Training the anaerobic system plays an important role in improving an individual's tolerance to lactic acid build-up and therefore their ability to cope with the stop-start nature of many sports.

Meeting the demands of the sport

Sports such as football, rugby, basketball and hockey involve intermittent exercise with bouts of short, intense activity breaking up longer periods of low-level, moderate-intensity exercise. In football about 75-90% of the body's total energy expenditure and consumption come from the aerobic system and although high speed actions only contribute around 11% of the total distance covered, they generally are the key moments of the game that directly contribute to goal scoring opportunities. Consequently, football (and other games sports) uses a combination of aerobic and anaerobic metabolism, alternating between intense work and active recovery.

It is essential that interval training mimics the physical demands that are encountered during match play. There is no use sprinting for distances and durations that are not related to the sport and clearly both aerobic and anaerobic energy systems must be stressed. The following interval sessions provide a range of sprint distances, speeds and inclines, with varying periods of active recovery. Although match situations are ultimately the best way to improve sport-specific fitness, these structured interval sessions can act as an effective alternative.

Example interval sessions

The interval sessions below are designed for a treadmill. However, they can be applied to other exercise machines or field based training. There are eight different sessions, which look to target the aerobic system, anaerobic system or a combination of both. Sprint and recovery speeds are suggested. However, they should be adjusted according to your ability in terms of fitness and speed capacity.

Interval Track Session (Glyolytic 1)

Interval Treadmill Session (Glyolytic 2)

Sprint speed

Maximum

Sprint speed

Maximum 14-20kmh (minus 1kmh each block)

Recovery speed

Light Jog

Recovery speed

Light Jog/ 7-10kmh

Sprint

Recovery

Sprint/Incline %

Recovery

60 secs

180 secs

60 secs/1.0%

180 secs

40 secs

120 secs

40 secs/2.0%

120 secs

30 secs

90 secs

30 secs/3.0%

90 secs

20 secs

60 secs

20 secs/4.0%

60 secs

10 secs

30 secs

10 secs/5.0%

30 secs

Complete 4 times with 2 minutes rest between each block

Complete 4 times with 2 minutes rest between each block

Interval Track Session (Oxidative 1)

Interval Treadmill Session (Oxidative 2)

Sprint speed

70-75 MHR%

Sprint speed

75-90% MHR

Recovery speed

Light Jog

Recovery speed

7-10kmh

Sprint

Recovery

Sprint/Incline %

Recovery

60 secs

60 secs

60 secs/1.0%

180 secs

40 secs

40 secs

40 secs/2.0%

120 secs

30 secs

30 secs

30 secs/3.0%

90 secs

20 secs

20 secs

20 secs/4.0%

60 secs

10 secs

10 secs

10 secs/5.0%

30 secs

Complete 4-6 times with 2 minutes rest between each block

Complete 4-6 times with 2 minutes rest between each block

Alternatively, in terms of heart rate

For the glycolytic sessions, sprints should work you to 80-90% max heart rate (MHR), the oxidative session sprints should work you to 75-85% MHR and the mixed session sprints should work you between 75-90% MHR.

All of the sessions involve active recovery, which should be a very slow jog. In sessions where the gradient increases by 1% for each block, the maximum sprint speed should decrease by 1% each time. In sessions that involve varied sprint speeds, ensure that there is at least 1km/h difference between each speed (medium, fast, and fastest), so don't start too fast!